It is the fifth time Davis, 74, was recommended for release by a parole panel, only to see the application rejected by a state governor. The parole panel had approved his latest request for release in February.

Davis was convicted in 1972 of the murders of musician Gary Hinman and stuntman Donald "Shorty" Shea in 1969 and sentenced to life in prison.

He was a follower of failed musician and cult leader Charles Manson, whose followers committed a series of brutal murders in California in the late 1960s.

Davis was not accused of involvement in the notorious murder of pregnant actress Sharon Tate, the wife of director Roman Polanski, and six others by Manson followers in 1969.

In his written decision outlining his reasons for refusing Davis parole, Brown acknowledged that Davis had spent 25 years in prison with no record for misconduct, and made significant efforts to reform his character.

Behind bars Davis has earned a doctoral degree, converted to Christianity, and ministers to other inmates.

"These cult murders have left an indelible mark on the public — the Manson Family is still feared to this day," Brown wrote, reported Associated Press. "Incredibly heinous and cruel offenses like these constitute the 'rare circumstances' in which the crime alone can justify a denial of parole."

Also, Brown added, "his continued minimization of his own violence and his role in the Manson Family further shows that he remains an unreasonable risk to the public."

Brown’s decision came after California authorities on Thursday denied parole—for the fourteenth time—to Manson follower Patricia Krenwinkel, 69. She argued that battered person syndrome affected her state of mind at the time of the killings.

"The ice doesn’t care what this administration thinks. It’s just going to keep melting," David Titley, the director of the Center for Solutions to Weather and Climate Risk at Penn State, told Newsweek.